clean-up libutils includes

moved Foo.h as first include of Foo.cpp, and
removed redundant includes.

Made NativeHandle non virtual.


Test: run & compile
Bug: n/a

Change-Id: I37fa746cd42c9ba23aba181f84cb6c619386406a
diff --git a/libutils/Tokenizer.cpp b/libutils/Tokenizer.cpp
index 2d0e83d..b68a2cf 100644
--- a/libutils/Tokenizer.cpp
+++ b/libutils/Tokenizer.cpp
@@ -16,14 +16,10 @@
 
 #define LOG_TAG "Tokenizer"
 
-#include <stdlib.h>
-#include <unistd.h>
+#include <utils/Tokenizer.h>
 #include <fcntl.h>
-#include <errno.h>
-#include <sys/types.h>
 #include <sys/stat.h>
 #include <utils/Log.h>
-#include <utils/Tokenizer.h>
 
 // Enables debug output for the tokenizer.
 #define DEBUG_TOKENIZER 0